Ewing sarcoma is a rare and highly aggressive neoplasm that occurs most frequently in male adolescents. The incorporation of neoadjuvant therapy and new surgical techniques has improved survival. We present the case of a 41-year-old man diagnosed with Ewing sarcoma of the chest wall, whose tumor showed a pathological complete response to a multimodal treatment consisting of concurrent chemotherapy, radiotherapy, and surgical resection. Ewing sarcoma rarely occurs in adults, who generally have a worse prognosis. A multimodal approach for the treatment of patients older than 40 years has proven to improve oncological results.